Added Post update function

app/controllers/posts_controller.rb

@@ -36,6 +36,15 @@ class PostsController < ApplicationController
   	@post = Post.find_by(id: params[:id])
   end
 
+  def update
+  	@post = Post.find_by(id: params[:id])
+  	if @post.update(post_params)
+  		redirect_to posts_path, notice: "You have successfully updated a post."
+  	else
+  		render 'edit'
+  	end
+  end
+
   private
   	def post_params
   		params.require(:post).permit!